• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.506-509
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• 2014

This study was conducted to identify transition characteristics of mercury in several selected medicinal plants and to find the appropriate management for production of safety food. Cultivated soils and medicinal plants were collected at 29 sites for Angelica gigas (Korean angelica root), 68 sites for Platycodon grandiflorum (Balloon flower), 35 sites for codonopsis lanceolata (Deoduck), 36 sites for Dioscorea batatas (Chinese yam), 32 sites for Rehmannia glutinosa (Foxglove), 16 sites for Cnidium officinale makino (cnidium), and 26 sites for Astragalus membranaceus (milk vetch root) during the harvest season of 2013. Mercury in the soils and medicinal roots were analyzed with a Direct Mercury Analyzer. Average content of mercury in soils cultivated medicinal plants was $0.023mg\;kg^{-1}$ (range: from 0.003 to $0.074mg\;kg^{-1}$) and average content of mercury in medicinal plants was $0.003mg\;kg^{-1}$ (range: from 0.001 to $0.011mg\;kg^{-1}$), indicating that mercury in the surveyed soils and medicinal plants were not exceeded the Korean regulation.

• Steel and Composite Structures
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• v.44 no.4
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• pp.587-602
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• 2022

In this study, the classical J₂ flow theory is explicitly proved to be inappropriate to describe the plastic behaviour of structural steels under different stress states according to the reported test results. A numerical framework of the characterization of the strain hardening and ductile fracture initiation involving the effect of stress states, i.e., stress triaxiality and Lode angle parameter, is proposed based on the mechanical response of structural steels under monotonic loading. Both effects on strain hardening are determined by correction functions, which are implemented as different modules in the numerical framework. Thus, other users can easily modify them according to their test results. Besides, the ductile fracture initiation is determined by a fracture locus in the space of stress triaxiality, Lode angle parameter, and fracture strain. The numerical implementation of the proposed model and the corresponding code are provided in this paper, which are also available on GitHub. The validity of the numerical procedure is examined through single element tests and the accuracy of the proposed model is verified by existing test results.

• Journal of Pharmacopuncture
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• v.17 no.4
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• pp.36-49
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• 2014

Objectives: Quercetin and curcuminoids are important bioactive compounds found in many herbs. Previously reported high performance liquid chromatography ultraviolet (HPLC-UV) methods for the detection of quercetin and curcuminoids have several disadvantages, including unsatisfactory separation times and lack of validation according the standard guidelines of the International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use. Methods: A rapid, specific, reversed phase, HPLC-UV method with an isocratic elution of acetonitrile and 2% v/v acetic acid (40% : 60% v/v) (pH 2.6) at a flow rate of 1.3 mL/minutes, a column temperature of $35^{\circ}C$, and ultraviolet (UV) detection at 370 nm was developed. The method was validated and applied to the quantification of different types of market available Chinese medicine extracts, pills and tablets. Results: The method allowed simultaneous determination of quercetin, bisdemethoxycurcumin, demethoxycurcumin and curcumin in the concentration ranges of $0.00488-200{\mu}g/mL$, $0.625-320{\mu}g/mL$, $0.07813-320{\mu}g/mL$ and $0.03906-320{\mu}g/mL$, respectively. The limits of detection and quantification, respectively, were 0.00488 and $0.03906{\mu}g/mL$ for quercetin, 0.62500 and $2.50000{\mu}g/mL$ for bisdemethoxycurcumin, 0.07813 and $0.31250{\mu}g/mL$ for demethoxycurcumin, and 0.03906 and $0.07813{\mu}g/mL$ for curcumin. The percent relative intra day standard deviation (% RSD) values were $0.432-0.806{\mu}g/mL$, $0.576-0.723{\mu}g/mL$, $0.635-0.752{\mu}g/mL$ and $0.655-0.732{\mu}g/mL$ for quercetin, bisdemethoxycurcumin, demethoxycurcumin and curcumin, respectively, and those for intra day precision were $0.323-0.968{\mu}g/mL$, $0.805-0.854{\mu}g/mL$, $0.078-0.844{\mu}g/mL$ and $0.275-0.829{\mu}g/mL$, respectively. The intra day accuracies were 99.589%-100.821%, 98.588%-101.084%, 9.289%-100.88%, and 98.292%-101.022% for quercetin, bisdemethoxycurcumin, demethoxycurcumin and curcumin, respectively, and the inter day accuracy were 99.665%-103.06%, 97.669%-103.513%, 99.569%-103.617%, and 97.929%-103.606%, respectively. Conclusion: The method was found to be simple, accurate and precise and is recommended for routine quality control analysis of commercial Chinese medicine products containing the flour flavonoids as their principle components in the extracts.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.4
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• pp.465-474
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• 2005

This study was conducted to estimate the contents of heavy metals 'mercury(Hg), cadmium(Cd), lead(Pb), arsenic(As), zinc(Zn), copper(Cu), chrome(Cr) and manganese(Mn)' in root vegetables which were produced in Korea. The levels of heavy metals were determined using a mercury analyzer, an ICP(inductively coupled plasma spectrometer) and an AAS(atomic absorption spectrophotometer) after wet digestion. The values of heavy metals 'mean(minimum-maximum)' mg/kg(ppm) in root vegetables (radish, turnip, carrot, ginger, edible burdock, taro, Chinese yam, east indian lotus) were as follows ; Hg : 0.0019(0.0002${\~}$0.0062), Cd : 0.0088(ND${\~}$0.0402), Pb : 0.021(ND${\~}$0.1070), As : 0.0401(ND${\~}$0.1732), Zn : 1.865(0.4186${\~}$6.9319), Cu : 0.648 (0.1826${\~}$4.0172), Cr : 0.121(0.0132${\~}$1.2030), and Mn : 2.730(0.0477${\~}$10.0468) mg/kg. These results showed that Hg were generally similar to and Cd was lower but Ph, As, Zn, Co, Mn were little higher than the levels of those reported contents in root vegetables on retail markets in Korea. Although the tolerable limit of Cd and Hg is not set in a regulation of WHO/FAO, the tested mean levels(Pb, As, Zn, Cu) were lower than the regulated ones of WHO/FAO, Pb '0.1-2.0', As '1.0', Zn '5.0', and Cu 0.1${\~}$50 mg/kg from vegetables. Therefore, root vegetables sold in the retail markets were evaluated as safe in terns of the heavy metal contents.

• Structural Engineering and Mechanics
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• v.78 no.4
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• pp.485-496
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• 2021

So far analytical methods on collapse assessment of three-dimensional (3-D) steel frames have mainly focused on a single-column-removal scenario. However, the collapse of the Federal Building in the US due to car bomb explosion indicated that the loss of multiple columns may occur in the real structures, wherein the structures are more vulnerable to collapse. Meanwhile, the General Services Administration (GSA) in the US suggested that the removal of side columns of the structure has a great possibility to cause collapse. Therefore, this paper analytically deals with the robustness of 3-D steel frames in a two-side-column-removal (TSCR) scenario. Analytical method is first proposed to determine the collapse resistance of the frame during this column-removal procedure. The reliability of the analytical method is verified by the finite element results. Moreover, a design-based methodology is proposed to quickly assess the robustness of the frame due to a TSCR scenario. It is found the analytical method can reasonably predict the resistance-displacement relationship of the frame in the TSCR scenario, with an error generally less than 10%. The parametric numerical analyses suggest that the slab thickness mainly affects the plastic bearing capacity of the frame. The rebar diameter mainly affects the capacity of the frame at large displacement. However, the steel beam section height affects both the plastic and ultimate bearing capacity of the frame. A case study on a six-storey steel frame shows that the design-based methodology provides a conservative prediction on the robustness of the frame.

• Smart Structures and Systems
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• v.28 no.6
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• pp.745-760
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• 2021

Dynamic buckling of structure is one of the failure modes that needs to be considered since it may result in catastrophic failure of the structure in a short period of time. For a thin fiber-reinforced polymer (FRP) plate under compression, buckling is an inherent hazard which will be intensified by the existence of defects like holes, cracks, and delamination. On the other hand, the growth of the delamination is another prime concern for thin FRP plates. In the current paper, reinforcing the plates against buckling is realized by using SMA wires in the form of stitches. A numerical framework is proposed to simulate the dynamic instability emphasizing the effect of the SMA stitches in suppressing delamination growth. The suggested algorithm is more accurate than the other methods when considering the transformation point of the SMA wires and the modeling of the cohesive zone using simple and yet reliable technique. The computational design of the method by producing the line by line orders leads to a simple algorithm for simulating the super-elastic behavior. The Lagoudas constitutive model of the SMA material is implemented in the form of user material subroutines (VUMAT). The normal bilinear spring model is used to reproduce the cohesive zone behavior. The nonlinear finite element formulation is programmed into FORTRAN using the Newmark-beta numerical time-integration approach. The obtained results are compared with the results obtained by the finite element method using ABAQUS/Explicit solver. The obtained results by the proposed algorithm and those by ABAQUS are in good agreement.

• Smart Structures and Systems
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• v.31 no.3
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• pp.213-227
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• 2023

A passive prismatic-shaped isolation platform (PIP) is proposed to realize enhanced quasi-zero stiffness (QZS) effect. The design concept uses a horizontal spring to produce a tunable negative stiffness and installs oblique springs inside the cells of the prismatic structure to provide a tunable positive stiffness. Therefore, the QZS effect can be achieved by combining the negative stiffness and the positive stiffness. To this aim, firstly, the mathematical modeling and the static analysis are conducted to demonstrate this idea and provide the design basis. Further, with the parametric study and the optimal design of the PIP, the enhanced QZS effect is achieved with widened QZS range and stable property. Moreover, the dynamic analysis is conducted to investigate the vibration isolation performance of the proposed PIP. The analysis results show that the widened QZS property can be achieved with the optimal designed structural parameters, and the proposed PIP has an excellent vibration isolation performance in the ultra-low frequency due to the enlarged QZS range. Compared with the traditional QZS isolator, the PIP shows better performance with a broader isolation frequency range and stable property under the large excitation amplitude.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.4
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• pp.61-76
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• 2006

Purpose : This study examined the non-toxic and the anti-oxidative effect of Dioscoreae Rhizoma on PC12 cells. Sanyak(Dioscoreae Rhizoma; chinese yam, shan yao) is well-known for its curing power for kidney, lung, spleen. Tonifies and augments the spleen and stomach. Tonifies the lung gi and augments the kidney yin. Tonifies the kidneys and also stabilizes and binds. it also binds the essence and treats spermatorrhea, frequent urination, and vaginal discharge. We are therefore interested in whether Dioscoreae Rhizoma is capable of causing abnormal apoptosis processes, and whether this condition can be rectified through Dioscoreae Rhizoma herb treatment. Methods : We used aqueous extract to treat PC12 cells with different concentrations treated with a water or a MeOH extract of Dioscoreae Rhizoma (0, x10, x20, x40, x80). The MTT (3, (4, 5-dimethyl-thiazol) 2, 5-diphenyl-tetraxolium bromide) reduction assay was employed to quantify the differences in cell activity and viability. The Bax expression level was monitored using western-blotting techniques. The patterns of the changes in expression were scanned and analyzed. Results : Bax and GSK-3${\beta}$ promotes cell death and down-regulated during the development of the PC12 cells. This is indicated that Dioscoreae Rhizoma is capable of inducing apoptosis in PC12 cells. The induced cell death and significantly inhibited by Dioscoreae Rhizoma, which can be explained by the increase in the inhibition of Bax and GSK-3${\beta}$ expression. It was also shown that Dioscoreae Rhizoma inhibits the release of $H_2O_2$ and prevents lipid peroxidation. Furthermore, the accumulation of wild type Bax protein significantly downregulated in a dose-dependent manner upon treatment with Dioscoreae Rhizoma. Conclusion : In conclusion, Dioscoreae Rhizoma can induce apoptosis via a Bax-dependent pathway or GSK-3${\beta}$ dependent pathway in PC12 cells into anti-oxidant and protective effect.

• Journal of Practical Agriculture & Fisheries Research
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• v.13 no.1
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• pp.173-183
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• 2011

Gabensis village is one of the biggest village In the Wampar Local Level Government area within the Huon Gulf District of Morobe Province with a population of around 3,000. The major staple food is banana which is well complemented by minor staples yam, cassava, Singapore/Chinese taro and sweet potato. Apart from gardening for own consumption, the villagers engage in selling of vegetables, garden staples, cocoa beans, coconuts, timber, chicken, fish and pig meat to supplement their livelihood. Livestock like pigs and chickens are also kept for meat and for commercial purpose. Bettlenut which was once one of the main cash crops has now been overtaken by cocoa due to a disease that had attacked almost the entire bettlenut tree population in the area. Even though the Wau-Bulolo highway cuts through the village and all have access to transport infrastructure, the majority of the population still encounter problems in communication due to poor telecommunication coverage. On average most people earn not more than K50 per week due to constrains in production and marketing among others. Gabensis village has the potential to develop a tourism industry given its natural attraction of Lake Wanam. Beside there is also the natural eel farming and the fish pond at the nearby Potsie village. These natural attractions pose huge tourism potential for the community. As part of government services delivery and development, education and health issues is very much important in the community however there is lack of infrastructural development and poor service delivery especially in the area of health. However, the responsibility is on the community to organize themselves to realize that potential. A well developed agro-ecotourism investments would have positive spillover effects to the community thus contributing towards improving the livelihoods of the many farming families.

• Journal of the Korean Society of Food Culture
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• v.18 no.6
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• pp.601-612
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• 2003

In Korean history, vegetables were the major side dishes of meals and originally korean diets were based on vegetables. But recently people prefer meat dishes rather than vegetables and traditional vegetable cooking seems to be disappeared. So it is needed to be positioning the importance of vegetables in food culture of Korean. In present study, history of vegetable eating was reviewed and recent consumption pattern were analyzed. 1. Since the era of the three Kingdom's and Koryo dynasty, the kinds of vegetables varied and at Chosun Dynasty people used similar kinds of vegetables as nowadays except a few things. A Garlic and mug wort had been used from the age of tribes to present and an egg, apple, cucumber, lettuce from the three Kingdom and a bamboo sprout, a taro, a burdock, a radish, a turnip, a stone-leek, a scallion, a Chinese cabbage, a marsh mallow, a spinach and a crown daisy from Koryo Dynasty and a pepper, a pumpkin, a tomato, a cabbage, a salary, a kale, a turnip and a beet from Chosun Dynasty to present. A guard, a water shield plant, a yam and wild plants would have been used before but they would not use any more. 2. Current vegetable consumptions of Korean is 232.2kg/person/yr and comparing with world mean consumption(101.9kg), Koreans still eat the largest amount of vegetables than any other countries and among Asian countries, Koreans consume more vegetables than China(203.5kg) and Japanese people(111.6kg) do. 3.The most frequently consumed vegetables were vegetables for seasonings such as a garlic or stone-leek and for kimchi such as a Chinese cabbage, radish, and carrot. But from data of Korean National Health and Nutrition Survey(2001), kinds of vegetables which people had were only 72 items showing that the kinds of vegetables were limited. 4. A lot of wild plants that would have been used for famine relief are now disappeared and on the other hand, it is increasing of some new and foreign vegetables and herbs. Cooking methods and intake pattern of vegetables are changed and varied so a traditional cooking method such as namuel is less preferred than before. But vegetable wrapping and green vegetable juice, eating uncooked vegetables(sang-sik) are very popular.